Refrigerating apparatus



1,628 820 May 17'1927 c. R. BUSHNELL REFRIGERATING APPARATUS Filed May l5, 1924 754 27 .53 D K 'fi .1.

Patented May 17, 1927.*

UNITED STATES PATENT OFF-ICE.

REFBIGERATING APPARATUS.

Application led Hay `1.5,

My invention relatesto and has for its purpose the provision of amethod of-refrigeration, which consists in compressing air, cooling the air through the latent heat of evap oration vof a liquid, and then allowing the air to expand in thermal relation to a. retrigen ant whereby a further cooling of the air is e'ected and a great reduction in the temperature of the refrigerant.

It is also a purpose of my invention to provide a refrigerating apparatus by means ofwhich the above method can he carried out, the apparatus having the following advantages: An apparatus requiring a rela tively small space andcapable of being operated at a relatively lowcost; an apparatus in which compressed air is employed as the refrigerating medium and meansby .which the moisturein `the refrigerating medium is eliminated to insure proper operation of the machine; an apparatus in which the air conn pressed is utilized in its expansion to operate a turbine for creating forced circulation of airI over pipes of the abstractor embodied in the apparatus; utilizing the compressed air to agitata and, circulate brine or a similar refrigerant through pipes to dissipate heat. in a refrigerating chamber; and an appa-- ratus in which the turbine previously nieu tioned is operatively connectedwith the com-- presser to aid the latter in compressing the ain and placing Athe turbine in circuit cornu munication with. the compressor whereby the initial air supplied to/the apparatus is reused inde-tinitely. o

I will describe only one method of refrigeration and two refrigerating apparatuses, each embodying my invention, and will then point out the novel features thereof in u claims A 1n the accompanying drawings- Figure 1 is-a view showing in vertical secm tion one form of refrigerating apparatus ernbodying my invention;

' `Fgure 2 is an enlarged sectional view otV one ot the pipes of the abstractor shown in v Figure 1t `Figure 3 is an enlar ed fragmentary sectional view ofthe Adisc arge end of the a'ir conduit andthe manner in .which'it is associaed with the intake end ofthe ooo-ling CO1 f Figure 4 is an enlarged fragmentary sec- 1924. Serial No. 718,537.

tional view of one of the compressor units shown lin Figure 1;

Figure 5 is a fragmentary sectional view showing a slightly modiiied form of refrigerating apparatus also embodying my `inven- 4 Referring specifically to the drawings, in which similar referencecharacters refer to similar parts, my invention in its'present embodiment is shown in Figure 1 as comprisin a casingl C preferably constructedL with double walls between which is interposed a `heat insulating material 15, and upon this casing 'is supported the compressor and ab-v stractor embodied in my invention. The compressor, comprises9 inthe present instance, a pair of compressingunits designated generally at K andK, and` these units are simultaneously operated by a motor M through the medium of a gear 16 fixed to the motor' shaft and meshing with a relatively large gear 17 fixed to a shaft 1S provided 4 with a crank 19 engaging' the cam memher 2() connecting the confronting ends of a pair of iston rods 2L tilach `conunessor unit K or comprises a cylinder 22 having a re movable i'iead 2d provided 'with a stuffing hox through which moves the corresponding piston rod 2l., The and ci the rod 21 is provided with a, piston head 24 which. moves in the cylinder 22 tor compressing air when moved in either direction. The cylinder 22 is provided with aporous Water iaclret 25 to which. Water is supplied hy means or a pipe 26, the porosity oit the. jaclret allowing the slow seepage 'uit Water outwardly through the jacket for the purpose of permitting scrumn ration and to thus utilize the latent heat of evaporation :tor cooling the cylinder and the `com ressed' air contained therein.

e ahstractor cmhedied iumv invention comprises pipa units vand P, and each unit consista ot two coils 'of ipe arranged one above the athen and, wit the-coils of the unit lil heing arranged above the coils of the 'unit P. The up er coil 27 of the unit P communicates wit the cylinder 22 .of the unit K'through a pipe 28, and a valve 29 allows the passage of compressed air into the pipe from the cylinder but prevents the dischargeof air back into the cylinder. Itis to be' noted that in Figure 1 the valves for the cylinders of the the outer end of tid ' construction of the valves .for the cylinder lIn of the unit Kj'vare shown in detail. The other end of the coil 27 is connected to one end ofthe .lower coil of the unit P and .this latter coil communicates with the outer end ofthe cylinder 22 of the unit K'. -As vshown in Figure 4, a valve.31 allows the exhaust of air from the coil 30 into the cylinder 22, but prevents. the retrograde movement of the air back into-.the pipe. In

. this manner the coils of the pipeunit P are placedin communication with the cylinders of both compressorunits so that the air compressed int e first unit K is conveyed to the second unit K'. As shown in Figure 1, a

branch pipe 32 connects the ipe 28 with the cylinder 22 of the unit'K4 at the inner end of the cylinder 22,'and this ipe'is provided with.` a valve 433 (Figure 4 which allows the passage 'of compressed air from the cylinder into the pipe 28, but prevents discharge of air backward into the cylinder. Bythis arran ement it will be seen that the air compresse by the piston 24 of the unitl YK' in moving to the Aright as when viewed in Figure`1, will find its way to the coil 27 through the pipes 32 and 28,

The upper coil 34 ofthe ipe unit P communicates at one lend wit the outer end o f the vcylinder22 of the unit K', and as shownin Figure 4 a valve 35 allows the passage of compressed air from the cylinder -into the coil, but prevents discharge' of lair from the coil into the cylinder. The opposite end of the coil 34is in communication with the lowercoil 36 of the unit P and from this lower coil a pipe 37 .extends downwardly through the top wall of the casing C into a tank T containing brine or a similar refrigerant. The lower end of the pipe 37 is provided with a restricted discharge port 38 (Figure 3) which'is disposed within the funnel shaped end 39 of a coiLpipe 40, the latter being arranged within the casing C and having its opposite end extended into and communicatingwith the upper portion of the tank T so `that the tank-1s in circuit communication with the coil.l The ipe 37 is provided with a branch pipe 4l w ich is in eommunicationwith the housing 42 of a turbine including a plurality of stator and rotor elements 43 which are provided with coacting vanes. 'Ihe air'entering the housing 42 acts on the vanes to effect rotation .of a shaft 44 which extends upwardly from the housing through the up er wall of the casing, where it is provide with a fan 45 disposed directly below the pipe units P and P for creating, when rotated, a circulation of air upwardly over the coils."l The air, after acting*` on the vane elements of the turbine,

is discharged from the housing through a pipe 46, auch pipe extending upwardly ythrough the casing and along the top wall thereof for communication withy the cylinder 22 of the units K through one way valve 47.

`with a'branch pipe `49 in communication .with the inner end of the .cylinder 22 of the unit K through a one-way .valve (Figure 4), the valves 47 and 50 operating to allow air discharged from the turbine to be rcturned to the cylinders of the compressor units.

The air discharged 'through the port 38 and into the coil of pipe 4() functions to effect a forced circulation of the brine in thetank T through the coil 'so as to be finally discharged back into the tank from the upper end of the coil. The air returned to the tank 'l is conducted fromv the tank to the cylinder 22 ofthe unit K through a pipe 5l, a valve 52 prevent-ing the return of i air lfrom the cylinder back into' the pipe.

with theinterior of the cylinder jackets 25 (as shown in Figure 4) so that water supplied to the latter by means of the pipe 26 will be free to circulate around the pipes. The jackets J are formed o f porous material to allow the slow seepage of water therethrough with the consequent rapid evapora.- tion of the water s that the latent heat of evaporation can be used in extracting heat from the compressed air traversing the pipes. In connection with the coils of the units P and P' evaporation of the water in the jackets is greatly aided by the current of air generated by the rotating fan 45. For the purpose of subjecting the jackets 25 of the cylinders 22 to currents of air, the absorber and compressor are provided with a cover 53 formed at its ends with openings 54 which allow air to` pass into and move horizontally across the water jackets under the action of the fan 45.

To provide an additional cooling action in that portion of the casing C in which the coil 40 is located the easing C is `irovided with partitions 55 and 56 arranged to substantially enclose the brine tank T. These partitions are formed with openings 55a and 5.6, respectively, which allows the circulation of air upwardly past the coil 40 and then downwardly over the surface of the tank T. 'lhe tank T may be provided with a pipe 57 which functions as a gage to determine lli the levell of brine within the tank. The .housing 42 is likewise provided with a pipe 58 whichextends exter1orly of the casing C for the purpose of draining moisture from the housing. A ressure regulating valve 59 is provided in tiie pipe 37 which is adapted to remain closedunt-il a predetermined pressure of air is built up in the -pipes of absorber, when the valve automatically opens and thus allows the compressed air to be suppliedto the turbine and tank. The pipe 61 provided with'a valve 6l constitutes an exhaust to atmosphere .for the cylinder 22 of the unit K through which air andmoisture is discharged from the cylinder andA preferably on to the coil 27 thereby providing an additional cooling mediumfortheair traversing the coil.

In yorder that the turbine may aid the motor M in actuating the compressor units,

I provide a train of gearing 6() which operativelyconnects the shaft 44with the shaft ofthe motor. In this manner the power of the turbine can be utilized to effectively assist the motor -i'n driving the compressor. t

The operation of' the followsz' Upon operation of the pistons 24 of the units K and K vthrough energization of the apparatus is as motor M, air isv admitted to the pipe 46 throu h the valve 48 and supplied to the cylindger 22 of the unit K. Under the re ciprocating action of the piston 24l the air in the cylinder-is com ressed and delivered to the unit P and fina ly-to the cylinder 22 ofthe unit K. During transit the com pressed air, whichfis naturally heated during operation, is materially reduced in temperature by virtue of the latent heat of evapora 'tion`of the Water lcontained in and seeping through the water jacket. This cooled air, after enterin the cylinder 22 of the unit K', is ejecte therefrom by the piston into the unit P', where it is subjected to the further cooling action of the latent heat of evaporation of the liquid surrounding .the coils 34 and 36. The super-cooled air is now delivered to the rotor and stator elements of the turbine for operating the shaft 44 to drive the fan 45 whereby a current of air is caused to traverse the coils of the units P and P' for aiding the evaporation of` the water. The compressed and super,a cooled air admitted to the housing 42 er;- pands andl in its propulsion of the rotor elements and in so doing effects an extraction of heat from the brine contained in the tank T, thereby greatly reducing the tern perature of the brine. The air admitted to the housing 42 constitutes fully a 'major part of the air traversing the pipe 37, the re mainder of the air discharging'from the port 38 into the coil 40 and thereby creating a forced circulation of the brine through the coil for reducing the temperature within the casing C. In traversing the coil'the temperature of the compressed air is in-4 creased, as will be'und'erstood. The air discharged from the housing42 and the tank T finds its Way back tothe cylinders 22 of the units K and -K for a second compression` and it is to be noted that by reason of the fact that the pipes 5l, 46 and 49 are provided with water jackets that the air traversing the pipes will be. further subject-ed to the heat extraction process by the latent heat of evaporation.

,From the foregoing description, taken in connection with the accompanying drawings, it will be manifest that I have provided a method of and apparatus 'for refrigerating in which compressed air in connection with brine or its equivalent are the sole refrigeratmg mediums, that the heat 1s extracted from the compressed air throughthe latent heat of evaporation of the water in the water jackets and the expansion of the air in the housing 42 of the turbine, and that a further extraction of heat from the brine is effected through its intimate association with the air in traversing the coil 40, and the provision of the water jackets surrounding the air return pipes to the cylinders of the compressor units. Further it will be manifest that after the air within the apparatus is compressed a predetermined degree the intatte valve 48 closes to prevent the further supply of atmospheric air to the apparatus, and that the compressor units, being in circuit communication with the turbine and brine tank, the air originally supplied to the apparatus' will be used and `reused indefinitely, By' using lthe original 46 is disconnected from the cylinders 22 of the units K and K for communication with atmosphere,l and for the purpose of cooling the surrounding atmosphere. a This modified form of my invention is particularly adapted for the cooling of the rooms of buildings, and

in this connection the coil 40 may or may not be used, as desired.

Although I have herein shown and described only one method of refrigeration and two forms of refrigerating apparatus, all embodying my invention, it is to be understood that various changes and modifications may be madev herein without de arting from the spirit of the invention. and t ie spirit and scope of the appended' elaims.

Having thus described myinvention, I claim:

1. A refrigerating apparatus comprising an air compressor, an abstractor incommunication with the compressor and comprising a water jacketed duct, the jacket of which is porous to permit evaporation of the water whereby tbe air from the compressor is cooled by the latent heat of evaporation of the Water, a turbine for creating a forced circulation of air over the abstractor, said turbine receiving the cooledair from the abstractor so as to be operated thereby, a tank confining a refrigerant in surrounding relation to the turbine, means by which the air delivered to the turbine from the abstractor is returned to the compressor, and means for operatively connecting the turbine to the compressor for aiding the latter in `compressing the air.

2. A refrigerating apparatus comprising an air compressor, means for extracting heat from the air compressor by the latent heat of evaporation of a liquid, a turbine for creating a forced circulation of air to aid the last means, a brine tank in surrounding relation to the turbine, a coil of pipe in circuit communication with the tank, and a pipe for delivering the cooled compressed air to the turbine for actuating the latter and having one end thereof arranged to discharge air into one end of said coil of pipe so as to create a forced circulation of the brine through the coil 0i pipe.

CHARLES RICHARD BUSHN ELL. 

